1. Field of the Invention
This invention relates to electronic communications, and more particularly, to a mobile communication device and method for reducing exposure to radio frequency energy during transmissions.
2. Description of Related Art
Mobile telephones and other wireless communication devices generate radio frequency (RF) energy during both outgoing and incoming transmissions. The main source of the RF energy is produced through the antenna of the device, which is typically either embedded in or affixed to the device itself. During a call, the antenna is often placed adjacent to the head of the user. The closer the antenna is to the head, the greater the level of exposure to RF energy.
The intensity of the RF energy emitted by a mobile telephone or other wireless communication devices depends on the strength of the radio signal sent to or from the nearest base station. When a call is placed from a mobile phone for example, a radio signal is sent from the antenna of the phone to the nearest base station. The base station routes the call through a switching center, where the call is transferred to another mobile telephone, another base station, or a landline telephone system. The farther the mobile telephone is from the base station, the higher the power level of the radio signal needed to maintain the connection. This distance determines, in part, the amount of RF energy exposure to the user.
A number of other factors also determine the amount of RF exposure to the user. These factors may include (i) the number of calls in which the user participates, (ii) the duration of the calls, (iii) the quality of the transmissions, (iv) the amount of traffic on the wireless network during the calls, and (v) the possible use of a hands-free device.
Currently there is a great deal of concern that RF energy produced by mobile phones and other wireless communication devices may affect the brain and nervous system of users. Since devices are usually held close to the head, medical researchers have focused on whether RF energy can cause either malignant or nonmalignant tumors in the brain, in and around the ears, the spinal cord and surrounding areas. Consequently numerous studies have been performed to investigate the relationship between mobile telephone usage and the risk of developing tumors. Although results of these studies have been inconclusive to date, the link between the use of mobile phones and cancer remains a significant fear.